Question

find 5he perimeter of sector if its measure is 90degree and radius 7cm. please give answer in full explaination.​

Answer 1

Explanation:

We have,

Angular speed ω=90rpm

Let the initial moment of inertia =I

75% of this M.I=43

Let the new angular speed be ω0

According to law of conservation of angular momentum,

43Iω0=Iω

43ω0=90

ω0=90×34

=120rpm